National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Mount Vernon Airport (KMVN)

Lat: 38.33°NLon: 88.85°WElev: 466ft.

Fair

64°F

18°C

Humidity 93%
Wind Speed Calm
Barometer 30.13 in (1020.4 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Last update 28 Aug 9:56 pm CDT
Extended Forecast for

Nason IL

  • Tonight

    Tonight: Patchy fog after 4am. Otherwise, clear, with a low around 64. Calm wind.

    Low: 64 °F

    Mostly Clear
    then Patchy
    Fog

  • Saturday

    Saturday: Patchy fog before 9am. Otherwise, sunny, with a high near 91. Calm wind becoming south southeast around 5 mph in the afternoon.

    High: 91 °F

    Patchy Fog
    then Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 68. Calm wind.

    Low: 68 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 95. Light south wind becoming south southwest 5 to 10 mph in the morning.

    High: 95 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 74. South wind 3 to 5 mph.

    Low: 74 °F

    Mostly Clear

  • Monday

    Monday: Sunny and hot, with a high near 98. South southwest wind 5 to 10 mph.

    High: 98 °F

    Hot

  • Monday Night

    Monday Night: Clear, with a low around 75. South wind around 6 mph.

    Low: 75 °F

    Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 99. Southwest wind 3 to 7 mph.

    High: 99 °F

    Hot

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 76. South wind 3 to 5 mph.

    Low: 76 °F

    Mostly Clear

Detailed Forecast

Tonight
Patchy fog after 4am. Otherwise, clear, with a low around 64. Calm wind.
Saturday
Patchy fog before 9am. Otherwise, sunny, with a high near 91. Calm wind becoming south southeast around 5 mph in the afternoon.
Saturday Night
Partly cloudy, with a low around 68. Calm wind.
Sunday
Sunny, with a high near 95. Light south wind becoming south southwest 5 to 10 mph in the morning.
Sunday Night
Mostly clear, with a low around 74. South wind 3 to 5 mph.
Monday
Sunny and hot, with a high near 98. South southwest wind 5 to 10 mph.
Monday Night
Clear, with a low around 75. South wind around 6 mph.
Tuesday
Sunny and hot, with a high near 99. Southwest wind 3 to 7 mph.
Tuesday Night
Mostly clear, with a low around 76. South wind 3 to 5 mph.
Wednesday
Sunny and hot, with a high near 98. Southwest wind 3 to 8 mph.
Wednesday Night
Mostly clear, with a low around 77. South southwest wind 3 to 5 mph.
Thursday
Sunny and hot, with a high near 99. Southwest wind 3 to 7 mph.
Thursday Night
A slight chance of showers and thunderstorms. Mostly clear, with a low around 76. Light south southwest wind.
Friday
Sunny and hot, with a high near 98. West southwest wind 3 to 6 mph.
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ABOUT THIS FORECAST

 
Point Forecast:
Nason IL
 38.18°N 88.98°W
Last Update:
9:41 pm CDT Aug 28, 2026
Forecast Valid:
10pm CDT Aug 28, 2026-6pm CDT Sep 4, 2026
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation